基于SIFT特征点匹配的水印图像几何校正算法.pdfVIP

第28卷第 6期 计 算 机 应 用 研 究 Vo.l 28 No. 6 2011年6月 ApplicationResearch of Computers Jun. 2011 S IFT* ( 广西财经学院计算机与信息管理系, 南宁 530003) : 为了有效实现水印图像的水印检测与水印嵌入之间的同步, 提出一种应用 SI T( scale invariant feature transform )特征点匹配估计水印图像几何变换参数的校正算法用两个稳定而又相距最远的图像 SI T特征点的 变化估计图像所经历的旋转和缩放参数, 校正之后, 再用 一个稳定的 SI T特征点的变化校正图像的平移变换 理论分析和实验结果表明, 该算法校正精度高性能稳定, 能有效恢复受到旋转缩放和平移攻击的水印图像的 水印同步,使水印算法能够正确检测或提取水印 : 水印图像; 几何攻击; SI T; 参数估计 : TP391 : A : 1001-3695( 2011) 06-2247-03 doi: 10. 3969 /j. issn. 1001-3695. 2011. 06. 068 New watermarked mi age geometric correction algorithm based on SI T feature pointsmatching LIAO Q i-nan (D ep t. of Compu ter Inf orm a tion M anagem en ,t G uangx i University of F inance E conom ics, N ann ing 530003, Ch ina Ab stract: In order to achieve the synchronization betweenw atermark detection andw atermark embedding, thispaper proposed amethod that estmi atedwatermarked mi age geometric distortion factors and corrected it by using SI T feature pointsmatching. Test mi age rotation and scaling parameters could be estmi ated by the difference bewt een the stable and the farther SI T feature point. s coordinates of it and that of the original mi age. A fter revising, the test mi age translation could be corrected by the change of one the stable SI T feature point. s coordinates of it and that of the original mi age. Theoretical analysis and exper-i mental results show that the algorithm has high correctional precision, stable performance, and it can recover w atermark syn- chronization ofw atermarked mi age by rotation, scaling and translation attacks effectively, so that thew atermark can be correctly detected and extracted. K ey word